Robert Crow was born in Shadwell, east London, to parents George Crow and Lillian Hutton.
He left school at 16 and went to work for Transport for London as an apprentice track worker.
From very early on he became involved in Union Politics, and at the age of 20 he was elected as a local representative to the National Union of Railwaymen.
In 1991 he became assistant general secretary of the Rail, Maritime and Transport Union, and in 2002 succeeded Jimmy Knapp as general secretary.
Often attacked by the right wing press for his militant action and living in a council house despite his six-figure salary, he was admired by members for fiercely defending their rights. Under his tenure membership swelled to over 80,000, making it one of Britain's fastest growing trade unions.
Often critical of both the Conservatives and Labour, he was labelled as part of the so-called 'Awkward Squad', a loose group of left-wing union leaders who came to prominence in the early 00s in opposition to the economically liberal polices of New Labour.
He held a combative relationship with London mayors Ken Livingstone and Boris Johnson and divided tube users over taking industrial action, the most recent of which being the February tube strike over the closure of ticket offices across the underground.
He died at the age of 52 on 11 March 2014 of a massive heart attack and aneurism. He is survived by his wife, Nicola Hoarau, a son and three daughters.